Humans have been harnessing the wind for thousands of years. Wind energy currently represents one of the most plentiful renewable resources on the planet. In recent decades as demand for additional sources of energy has increased, wind power has emerged as a clean, environmentally sustainable, renewable source of energy essential to the world's growing economy. Traditionally, wind energy has been captured and converted into usable electricity through the use of large wind turbines that drive a corresponding electrical generator. In most cases a plurality of wind turbines are placed strategically in an area of high and constant wind creating modern wind farms.
In a traditional wind power generation system, a generator is mounted onto a large tower that is erected to a sufficient height so as to capture wind energy to rotate a turbine. The rotation of this turbine is used to rotate a rotor placed in proximity to a stator which, when a magnetic field is applied generates an electrical current that may be diverted to a grid or used for other work. Traditional wind power generation systems typically use conventional gear configurations to “gear up” or “gear down” the system in response to varying wind velocities. While traditional systems have been employed commercially to some limited success, there are significant drawbacks to these systems. First, many commercially available traditional wind capture systems utilize only a single large generator mounted on top of a large tower, sometime in excess of 200 feet and may weigh as much as 150 tons. Despite the obvious problems of construction and weight distribution, as well as the disadvantages of having such a large single generator placed in an elevated position, maintenance is complicated in such a configuration. In addition, with only a single generator, any mechanical or other failure may result in the entire traditional wind power generation system needing to be deactivated while repairs are made.
Another drawback of traditional systems is that they often cannot operate at low or high wind speeds and as a result have a limited turbine RPM where they may operate. At low wind speeds traditional wind turbine generators often cannot generate enough mechanical power to innervate a single large generator. Typically, traditional wind turbine systems need to achieve at least 12 RPM to begin generating an electrical output. Below this RPM level such traditional wind turbine systems cannot generate sufficient mechanical energy to innervate such a large single generator efficiently and therefore generally need to maintain the generator in a disengaged position.
Conversely, traditional wind turbine systems often cannot efficiently operate during high wind conditions. Typically, traditional wind turbine systems often cannot exceed 20 blade RPM, which represents a limiting upper threshold. Under such high wind conditions, the mechanical energy generated from the rotating turbine can exceed the generator's capacity to operate effectively and may need to be disengaged. Traditional wind turbine systems can have conventional gearing systems to accommodate changes in wind velocity. Despite this they can be mechanically limited in the range of wind velocities where they can effectively operate. This in turn limits their operational efficiency and ultimately their overall commercial value.
Furthermore, traditional wind turbine systems often need to be shut down as often as twice per week to be cleaned and maintained. This extended and complex maintenance further reduces the economic viability and reliability of traditional wind turbine systems.
Another drawback of traditional systems is that in addition to being limited in their range of operation, electrical output and mechanical design, they can be prohibitively expensive in relation to the amount of actual usable electricity produced. As discussed previously, traditional systems can only be operable within a narrow window of available wind energy to drive the generator. For example, traditional wind power generation systems may contain a single 1.5 MW generator that produces 900 kilowatts (KW) at a blade speed of 12 RPM, and 1.5 MW at a blade speed of 20 RPM. Despite the need for additional energy sources, and despite the plentiful and ubiquitous nature of wind energy, this level of commercial wind power generation as compared to other more traditional methods such as hydroelectric and coal fired plants has not yet proved economically feasible on a large scale. Furthermore, traditional wind turbine systems can require large amounts of initial capital and manufacturing resources and, as discussed above can be limited in the amount, range and reliability of their wind powered electrical generation.
The foregoing technological and economic limitations associated with traditional wind power generation systems as well as wind power generation techniques associated with said systems may represent a long-felt need for a comprehensive, economical and effective solution to the same. While implementing elements may have been available, actual attempts to meet this need may have been lacking to some degree. This may have been due to a failure of those having ordinary skill in the art to fully appreciate or understand the nature of the problems and challenges involved. As a result of this lack of understanding, attempts to meet these long-felt needs may have failed to effectively solve one or more of the problems or challenges identified herein. These attempts may even have led away from the technical directions taken by the present inventive technology and may even result in the achievements of the present inventive technology being considered to some degree an unexpected result of the approach taken by some in the field.
Accordingly, there is a need within the field for an efficient and economically viable wind power generation system that addresses each of the technological and economic limitations outlined above. The inventive technology disclosed in this application represents a significant leap forward in the field of power generation and power generation systems.
The wind power generation systems discussed in this application among other attributes allows for generator control at the coupler level thereby allowing for constant generator RPM and electrical output at variable wind velocities, as well as constant generator output and RPM at wind velocities below and above traditional wind velocity thresholds. In addition, embodiments of the current inventive technology allow for increased and efficient sequential multi-generator wind energy capture at low turbine rotational RPM. Various embodiments of the current innovative technology may provide methods and apparatus for a wind power generation system wherein multiple generators are controlled and sequentially loaded and possibly adjusted along a continuum by a continuum coupler. Additional embodiments may include a radius adjustable coupler. Additional embodiments may include methods and apparatus for continuum coupling multiple generators to a rotational element such that said generator's electrical output, and RPM are controllably maintained thereby outputting a constant electrical output as well as increasing the overall efficiency of wind capture and energy conversion as well as increasing the range of wind velocities wherein sufficient wind energy may be captured to produce an electrical output.